Known end-dogging log carriage systems are disclosed by prior patent No. 4,697,487, granted Oct. 6, 1987, and entitled, "Adjustable Cable Driven Carriage System And Method," and by the patent documents listed therein. The main object of the present invention is to provide a relatively high speed log carriage system which is relatively lightweight and simple in construction. Another object is to provide a twin carriage system, composed of a pair of the improved carriages in a side-by-side arrangement. A further object of the invention is to provide an improved dog arm.